A search for point sources of high-energy neutrinos with the AMANDA-B10 neutrino telescope.

摘要

This dissertation describes a search for astronomical point sources of high energy neutrinos using the AMANDA-B10 detector. Good sensitivity is achieved over most of the northern hemisphere by tailoring the analysis to hard neutrino spectra (E-2) and relaxing signal purity requirements. This strategy, thus far unique in AMANDA, produces large effective area and the lowest flux limits. The data collected between April to November of 1997 (total of 130 days of livetime) has been analyzed. No point source candidates were identified. For sources with E-2 spectra, the detector achieves 10,000 m2 in average muon effective area between declinations of 35 to 90 degrees. Flux limits for declinations larger than +45 degrees are competitive with the best limits in the northern sky. Depending on zenith angle of the source, AMANDA flux limits for neutrino-induced muons range between 5--15 x 10 -15cm-2 sec-1 and neutrino flux limits vary between 5--15 x 10-8cm -2 sec-1 for neutrino energies between 101.0-7.0 GeV, assuming an E -2 energy spectra, but strongly depends on the assumed spectral index. Approximately 90% of the detected neutrinos from a source with E-2 spectra have energies between 10 3.0-6.0 GeV. The predicted sensitivity of AMANDA-B10 was confirmed by a detailed study of background events, direct observation of the atmospheric neutrino background, and SPASE-AMANDA coincident events. High multiplicity atmospheric muons were used to evaluate the response of the detector to muons at TeV energies. The predicted absolute pointing accuracy, angular resolution, and signal passing efficiencies has been confirmed by the analysis of coincident events registered by the SPASE air shower array and the AMANDA-B10 detector. Small offsets of 1° in absolute pointing are shown to negligibly impact flux limits. The impact of systematic errors on flux limits were determined by modifying detector related parameters such as OM average sensitivity and angular dependent sensitivity, ice models, etc. These studies confirm our predicted sensitivity to within 40%.